Re: [libvirt] [PATCH 5/5] libvirt_nss: Report newer addresses first

On Sat, Jul 13, 2019 at 12:58:38PM +0200, Michal Privoznik wrote: > Ideally, a software that's translating domain names would iterate > over all addresses the NSS returned, but some software does not > bother (e.g. ping). What happens is that for instance when > installing a guest, it's assigned one IP address but once it's > installed and rebooted it gets a different IP address (because > client ID used for the first DHCP traffic when installing the > guest was generated dynamically and never saved so after reboot > the guest generated new ID which resulted in different IP address > to be assigned). This results in 'ping $domain' not working > properly as it still pings the old IP address. Well, it might - > NSS plugin does not guarantee any order of addresses. > > To resolve this problem, we can sort the array just before > returning it to the caller (ping) so that the newer IP addresses > come before older ones. > > Reported-by: Andrea Bolognani <abologna(a)redhat.com&gt; > Signed-off-by: Michal Privoznik <mprivozn(a)redhat.com&gt; > --- ... > { > "ip-address": "192.168.122.254", > "mac-address": "52:54:00:3a:b5:0c", > "hostname": "gentoo", > - "expiry-time": 2000000000 > + "expiry-time": 2000000001 So, why is ^this specific change needed? In the test, you're expecting 192.168.122.[197-199], 192.168.122.199 has expiry time of 1900000000, so the test would still work. 192.168.122.254 is only assumed in a gentoo test twice, but there are no other addresses to sort in those cases, so the expiry time in there should not matter right? With the explanation of the above: Reviewed-by: Erik Skultety <eskultet(a)redhat.com&gt;